You should get more than 2h. Didn't try it on 5dmk3 but i got 2h on 550d on winter on one battery full charge.
April 20, 2014, 05:19:17 PM
Topic: How many minutes of video fit on a 32Gig CF card? (Read 1812 times)
I shoot with both the 60D and 5DIII and noticed that battery life is significantly shorter on the 5D. For a typical event shoot (video) I can get 2-3 hours on a 60D with a 2 year old battery, and about 1-2 hours on the same battery on the 5D.
I can just get a 48G card full with a bit on the battery indicator to spare, ( PS I turn the lcd to the lowest brightness)